Auxiliary suspension assembly for vehicles



Sept. 13, 1949. L. H. BRADLEY ETAL.

AUXILIARY SUSPENSION ASSEMBLY FOR VEHICLES Filed Sept. 28, 1944 2 Sheeis-Sheet 1 Sept. 13, 1949. L. .H. BRADLEY ET AL AUXILIARY SUSPENSION ASSEMBLY FOR VEHICLES 2 Sheets-Sheet 2 Filed Sept. 28, 1944 y 1 x mww M Tdw E N a m w; r an M m I 0 6 Y B a 5 a a z w 0 H W O A g 24 4 ((L Z Patented Sept. 1?, 1949 f AUXILIARY SUSPENSION VEHICLES ASSEMBLY FOR Leon H. Bradley, Independence, and James T.

. Jennings,

Jr., Kansas City, 7 Butler Manufacturing Company, Kansas Mo., assignors to City,

Mo., a corporation of Missouri Application September 28, 1944, Serial No. 556,157

Our invention relates broadly to suspension assemblies 01' resilient mountings for motor vehicles.

Springs having sufficient capacity to carry heavy loads are provided on trucks or tractor-;

When the vehicle is empty has littl or no resilient enacted laws limiting trailer combinations.

the Spring suspension effect. Many States have the legal laden .weight-- commercial vehicles, thus increasing the. permissible pay load. Vibrations resulting from unsprung weight during empty hauls have proven to be very destructive to equipment.

This problem has been particularly trouble-'1 some in vehicles having tanks mounted thereon. .Vibration causes crystallization of the metal resulting in leaks and other. body failures. This constitutes a definite fire hazard in the transportation of petroleum products.

We have accomplished an improvementin the conventional spring assemblies by the use of auxiliary resilient flexible mountings. The arrangement is simple in its construction and provides the vehicle when empty with resilient suspension. The auxiliary mountings are seated when the load is added and the resilient suspension is then provided by the main springs.

. The assembly is an improvement over the construction shown in Patent 2,245,382 dated June One'object of our invention is to provide vehicle spring assembly in which the vehicle body, when in an unloaded condition, rides on comparatively flexible resilient mountings which reduce destructive vibration.

Another object of our invention is to provide flexible resilient mountings, which seat when the vehicle is in a loaded condition.

A further object of our invention is to provide spring mountings of a'more' rugged construction than the auxiliary leaf spring mountings.

Other and further objects of our invention will Qappear from the following description.

In the accompanying drawings which form part of the instant specification and which are to be read in conjunction therewith, and in which like reference numerals are to be used to indicate like parts in the various views, I

I Fig. Us a side view of a tractor-trailer assembly showing a preferred embodiment of our invention,

Fig. 2 is a fragmentary top plan view of the front portion of the trailer showing the fifth wheel'arrangement, I

;Fig; 3: is .an enlarged 'd'etailview show-ingiithei These laws have prcmpted manufacturers to construct lighter 3 Claims. (oi. est-+) torsion type auxiliary mounting in combination with a rear Wheel spring assembly,

' Fig. 4 is an enlarged detail end view of the rear wheel suspension assembly shown in Fig. 3,

Fig. 5 is a view taken along the line 55 in I Fig. 2 in the direction of the arrows,

Fig. 3 in the direction of type mountings on the rear Fig. 6 is a view taken along the lines 6-6 in I the arrows,

Fig; 7 is a rear view'showing the'auxiliary shear springs of a vehicle,

Fig. 8 is a side view of one of the shear type mountings shown in Fig. 7.

Referring to the drawings, numeral I (l'designates the frame of a tractor attached to a trailer whose frame II supports twin tanks I2 as shown in Patent 2,192,593 dated March 5, 19%. The

rear end of the frame is mounted on sill members I3.

The rear wheel spring suspension assembly has uide brackets I4 riveted or otherwise fastened to sills I3. Each guide bracket assembly has a seating plate I 4a which forms the top of a housing Mb surrounding a connecting block l5. Con- I5 has depending wings l5a which straddle the end of spring I6 slidably supported on bolt I1. The springs II; are attached to axle I8 by means of U-bolts I9. The springs I6 are of the conventional type made up of a plurality of leaves of varying lengths.

Thetorsion element detailed in Fig. 6 consists of an inner cylinder 20 and an outer cylinder 2 I. The outer cylinder 2I has a flanged bracket 22 bolted to the sill I3. The annular space between cylinders 20 and 2| is filled with a tough resilient web of flexible material 23 which is rigidly bonded to the'surfaces of the respective cylinders. Rubher or synthetic rubber has proved satisfactory fifthwheel end of the as the resilient material for the web.

Inner cylinder 21! extends beyond cylinder 2 I at one end and to this extended end is adjustably attached torque arm 24. The opposite end of the torque arm 24 is aflixed to connecting block I5.

The front end of trailer II is carried by tractor In upon a conventional fifth wheel shown in Figs. 1 and 2. The fifth wheel assembly'has a lower friction plate 25 pivoted upon a cross shaft 26 which is carried by bolsters 21. Bolsters 21 are mounted upon the frame Ill of the tractor.

A king pin 28 mounted on an upper friction plate 29 fits into a slot form'e'd'i'n the lower'friction plate 25. This fifth wheel assembly is of the semi-automatic type conventional with this type of vehicle. Spring suspension for the front. or twin tank consists of the tractor leaf springs. If6 similar in constructionto ing transversely of the vehicle.

bolt ll. When empty springJ-S. The spring assembly ification is. clamped to axle I8 by U the rear trailer springs and resilient auxiliary mountings of the shear type designated by numerals 30 and 30a in Figs. 1 and 2. The shear type elements 30 and 30a are identical in construction except for size and are detailed in Fig. 5. ince the greater weight of the empty tanks is carried along the axis of the vehicle the auxiliary elements 30 are somewhat larger than the lateral elements 30a. similar in construction to having an inner cylinder 2 2i, and an annular web of flexible bonding ma-' terial 23. The functioning of the elements is the torsion elements however difierent in that the flexible material of the torsional element is put in stress by rotation of the inner cylinder while the shear type element is put in stress by movement axially? ofthe. inner cylinder with respect to the outer cylinder or shell. These elements are of similar construetion to the Vibro-Insulators manufactured by the-B. F. Goodrich Company. e 7

Upper friction plate 29 is fixedly mounted on the lower ends of the inner cylinders 25) of each of auxiliary resilient mountings or shear type elements. The outer cylinders 21 of elements 30 are fixedly attached. to cross bolstersf3i extend- The outer cylinders of elements 360. are attached to longitudinal braces 32 positioned between bolsters 3i. In the single tank or twin tank vehicles to lower the center of gravity, it maybe advisable to inset the elements incavities or pockets formed in the bottom of the tanks.

A modified. form or embodiment of our invention as applied to the rear trailer spring assembly is shown in Figs. '7 and 8 where the auxiliary resilient elements are of the shear type instead of the torsional type. The resilient. elements are here. positioned vertically in contrast with. the

horizontal positioning of the torsional type. In

' this modification the inner cylinderfli of the shear element is bolted into the top. of an open ended cylindrical housin 33 the walls of which surround and enclose the upper portion of the outer cylinder 21. These housings'33 are hung from the sills l3 of the vehicle by brackets 33a.

' The outer cylindrical shell of this shear type element is cup shaped. The bottom Zia, equipped with ears Zl'b by means of which the cylindrical spring end by supporting the weight of 'th'e tanks and frame is supported or carried by the flexible material 23 bonded to the cylinders and put in shear by relative movement of the concentric cylinders. When loaded the cylinders seating cup is attached to the against the top 33b of the housing 33 and against the bottom 2 la of the outer cylinder form a rigid connection to transfer. theweightof the loaded tanks directly from the sill l3 to the main H in this. mod- -bolts l9 carried by the axle on saddles. 34. i

The arrangement of the main spring l9 and the. auxiliary resilient mountings is: adapted tosupply asupplemental buoyant or resilient spring suspension of the trailer body when. thevehicle. is operating in an unloaded and a loadedcondition.

The auxiliary mountings are much more easily fiexedthan the main springs and supply the resilient suspension for the unloaded tank. An increase of the load imposes increased stress upon the resilient mountings until come seated. When seated. arigid.connection-- the mountings be- Elements 3!] and 30a are- 7 9, and outer cylinder is formed between the vehicle frameand main springs. r

The auxiliary suspension of the torsion type is more adapted to provide resilient suspension through a torque action given the flexible bondingv material and this is accomplished in the i01 lowing manner; Theweight' of the empty vehicle load is. transferred from S111 l3 to cylinder 2|.

Cylinder 29 receives the load through the web of resilient flexible material 23 and irregularities in the road surface are absorbed or neutralized in torquev or rotative twist given to the flexible the load from cylinder 'toconnecting block 11 to the wheels. sional twist. exerted 23 becomes greater,

.zf'erred directly through aconnection between guide bracket l4, plate l The main springs '25" resilient mountings time the Weight of the loaded trailer is transto and connecting; block i5 to spring l5.

iency when the vehicleis loaded. The auxiliary teammate only when the vehicle is empty.

'5 The auxiliary shear type elements on in Figs-7 and 8.

type mountings on the fifth wheel assemblly' operate the same as the shear Tractor It equipped with conventional springs it adapted to have optimum resiliency when carrying 'a loaded trailer; Obviously such springs are possessed with little or no resiliency when the trailer is empty. The load of the front ferred from the cross bolsters 3| through the shear type mountings to the upper The elements are partially positions when suspend j ofthe ing. the weight of the empty trailer. An increase I of the load. forces the outer cylinders downward until theyiseat against plate29. Simultaneously the inner cylinders closing plates. Thus-the seated mountings provide 4, and. fifth wheel assembly.

. novel spring assembly for motor vehiclesiin which vehicle operating either reducing to a minimum arigid connectionbetween the front of the trailer It will be seenthatgwe have accomplished the object of our invention.

'We have provided a we are able to. reduce vibrationalstresses upon a the principal causes-pf body or frame failures. J r

.: It will. be understood that certain. features. and

sub-combinations are of isv with-in the scope oi our claims.

I, tail-s within the. scope. of our claims without de-' It is" P thereforetobe understood utility and maybeemployed without referenceto'other featureslfand sub-combinations. This is contemplated by, and It is further obvious that various changes may bemade in departing from the spirit of our invention.

that our invention is not to be limited to the specific details shown and I: described. j

' Havingthusdescribed our invention, we claimi 1. A spring suspension'for'motor vehiclebodies frame and aXle construc-.

. tion, a spring mounted on the axle adapted to ,resiliently support the loaded. body,

an auxiliary resilient mounting enacting with saidspring to resiliently support the body in unloadedcondition, saidi auxiliary mounting. comprising a: bracket lowering sill l3 until plate Ma is seated upon connecting block l5. At this 7 1 t have their optimum. resilhave their optimum resiliency w the rear trailer springs-shown 3 trailer is trans and braces: 32

2t seatagai'nst the upper enempty or loaded; thus slidably connected to said spring, a torque arm attached to the bracket, concentric surfaces operably connected respectively to the frame and the torque arm, said surfaces bonded together with a web of flexible nonmetallic material, and a seat against which the bracket is adapted to bear when the nonmetallic material is in flexed condition due to the total load exceeding the weight of the unloaded body, said seat adapted to transfer the load to the spring through said slidable connection between the bracket and spring.

2. A spring suspension for a vehicle body having a frame and axle construction, comprising a leaf spring mounted on the axle adapted to resiliently support the loaded body, a pair of concentric cylinders bonded together with a web of flexible nonmetallic material, a rigid connection between one of said cylinders and the frame maintaining the axes of the cylinders substantially horizontal, a torque arm carried by the other cylinder and adapted to move in a vertical plane when said nonmetallic material is flexed, means providing a sliding connection between the free end of the torque arm and one end of the leaf spring permitting horizontal movement of the end of the spring relative to the end of the torque arm,the weight of the unloaded body being transmitted to the axle through said flexible material, torque arm, sliding connection and spring, and a vertical guideway on the frame at the junction of said torque arm and spring cooperating with said means to prevent movement of said sliding connection in a direction parallel to the axes of said cylinders.

3. A spring suspension as in claim 2 having a stop in said guideway limiting the upward movement of the torque arm, said stop effective to transmit the body load directly to said spring When the load exceeds a predetermined value.

LEON H. BRADLEY. JAMES T. JENNINGS, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,031,612 Anger July 2, 1912; 1,617,031 Schacht Feb. 8, 1927 2,027,990 Lubbers Jan. 14, 1936 2,125,184 Kjolseth July 26, 1938. 2,166,822 Parker July 18, 1939 2,198,616 Hickman Apr. 30, 1940 2,242,852 Flowers May 20, 1941 FOREIGN PATENTS Number Country Date 511,715 Great Britain Aug. 23, 1939 

